I was extremely luke-warm on the movies, but I did like the 3rd movie enough to start reading the books. At that point, the 6th book was just coming out, so I read up to the end of what was available. The 4th book ended up being my favorite, so I was pretty stoked when the 4th movie came out. Unfortunately, it was so badly transitioned from the book that I left 30 minutes into the film. I stopped caring about the movies after that.
I went on to finish the books and loved them quite a bit. I also got all the audio books read by Steven Fry, and they are amazing. I put them on my phone's MP3 player and just listen to them over and over while in the car.